1. Technical Field
The present invention relates to a voice command processing system and a computer therefor, and to a voice command processing method and program that improves the recognition ratio for user issued voice commands.
2. Description of the Related Art
Currently, many computer types are employed in diverse locations, and accordingly, various data input means are employed for these computers. Such input means include, for example, keyboards equipped with multiple keys, mice for pointing to arbitrary locations on monitors, touch pads for entering data by running a pen across a photosensitive surface, and speech recognition means for using a microphone to collect and enter as speech data words uttered by a user. Of these input means, the speech input means not only can recognize speech as characters (dictation), but also can understand a voice command issued by a user to enable a predetermined operation of an application. That is, since this speech input means can be used to enter voice commands for a computer or an application, the attention of people is especially drawn to the convenience of its use as input means.
For the recognition of a voice command, the speech of a user entered at a microphone connected to a computer is processed by a voice command recognition program executed by the computer. The voice command is defined using the BN method (Backus-Naur form), which is one of the context description representations for programs executed by the computer. When the voice command recognition program identifies a voice command that exactly matches the grammar of a voice command defined and registered in advance, a designated action is performed. That is, when a user exactly pronounces a voice command registered in advance, a desired action can be initiated.
Since a voice command is defined for each action, however, the possible number of command types are so numerous that it is difficult for a user to exactly memorize and pronounce all voice commands. Further, a user who is not sure of the commands may issue a different, incorrect voice command instead of a correct, registered voice command. Since the word order in a sentence is comparatively changeable, especially in Japanese, a user tends to issue an incorrect voice command, and since the incorrect voice command is not identified as a voice command and is not executed, the user is displeased because even though instructed, a desired action is not initiated.
There is another method used for the advance registration of voice commands that a user will be assumed to issue. According to this method, however, although the number of voice commands to be registered is increased and an extended period of time is allocated for the identification of a voice command, the recognition ratio still can be reduced.
To resolve these technical problems, the primary objective of the present invention is the provision of a voice command processing system that can increase both the degree of freedom for the pronunciation of a voice command by a user, and the recognition ratio for a voice command.